Cells As A Basis Of Life Flashcards
What structures do all cells possess?
All cells possess a cell membrane, cytosol (cytoplasm), ribosomes, and genetic material (DNA).
What structures make up a typical prokaryotic cell?
A prokaryotic cell is made up of a capsule containing a cell wall, cell membrane, cytoplasm, plasmids, and chromosomes. They also have pili and a bacterial flagellum.
Definition of Diffusion
The net movement of molecules from a high concentration to a low concentration until equilibrium is reached. Molecules move along a concentration gradient/slope.
Definition of Osmosis
The net movement of solvent molecules from high solvent concentration to low solvent concentration through/across a semi permeable membrane.
What is the equation for Photosynthesis?
Carbon dioxide + water —(light energy + chlorophyll)—> glucose + oxygen
6CO2 + 6H2O —> C6H12O6 + 6O2
How to answer an osmosis exam question
- State that during osmosis water always moves from a high concentration to a low concentration.
- Identify whether conditions are isotonic, hypertonic or hypotonic and state where water or solute concentrations are higher/lower.
- Identify direction of water movement
- Describe impact on cells; do they burst/swell/shrink etc
- What impact will this have on the living organism?
Distinguish between Isotonic, Hypertonic and Hypotonic
Isotonic = Both solute and solution are pf equal concentration; equal.
Hypertonic = Higher concentration of solute than solvent; concentrated.
Hypotonic = Lower concentration of solute, higher concentration of solvent; diluted.
Describe the function of the Mitochondria
Cellular respiration
The mitochondria is responsible for producing energy through the process of cellular respiration.
Mitochondria combine oxygen with sugars (cellular respiration) to release energy in a form (ATP) that the cell can use.
Functions of the mitochondria include: regulation of metabolic activity in the cell, ion homeostasis and programmed cell death.
Describe the function of the Nucleus
Storage of information
The nucleus stores the information needed to control all cell activities. It contains all DNA and genetic information necessary to control the cell’s function.
DNA replication, transcription and RNA processing all takes place in the nucleus.
Describe the function of the Golgi Apparatus (Golgi Bodies)
Packaging and sorting products
Golgi bodies process, package and sort cell products. They are involved in adding proteins and carbohydrates to cell products and provide a membrane around cell products to package them.
The three primary functions of the Golgi apparatus are the transport, sorting and modification of both proteins and lipid molecules.
Describe the function of the Cell Membrane
Controls the movement of substances into and out of the cell
The cell membrane controls the exchange of material between the internal and external environments of the cell. It is selectively permeable and the structure of the membrane works to allow specific molecules to enter and exit the cell through osmosis.
What is Endocytosis?
A process that involves the movement of a large amount of materials into a cell.
Endocytosis is a process used to import materials into the cell. Endocytosis occurs when the cell membrane changes its shape to surround the particle and engulf it, ultimately transporting it into the cell.
Endocytosis is needed when large particles may not be able to diffuse through the membrane like usual.
What is Exocytosis?
A process that occurs in order to expel large molecules out of the cell.
Exocytosis exports materials such as hormones and waste products outside of the cell. During Exocytosis a membrane bound vesicle moves to the cell membrane, fuses with it, and releases its contents to the exterior.
